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By the data on measured displacements at the boundary of a cylindrical underground opening (mine shaft), in the model of a perfectly plastic body, the authors assess deformation of rock mass around the opening and find the elastic-plastic boundary and displacements in the plastic deformation zone.

Gravity-induced lateral stress in rocks is assessed in the framework of physical simulation using a flexible thin-walled cylinder. Compression of loose geo-materials changes diameter of the cylinder, which allows estimating lateral stress. The observed dependences with various compacted geo-materials are then theoretically approximated based on characteristics of porosity, rock deformation modulus and Poisson’s ratio. The obtained relations are applicable to estimation of gravity-induced lateral stress in an intact rock mass.

Based on the developed procedure, experimental regularities are obtained for the formation of submicron particles under rock failure. The experiments involved explosion load on rock specimens and their uniaxial compression with the concurrent control over size and amount of particles until failure using laser spectrometry. It is found that most of all particles are formed in the size grade of a few microns irrespective of the kind of loading. Dynamics of the formation of particles depends on structural characteristics of specimens and on the value of the compression stress. The authors emphasize the promising nature of the experimental results usable both in the environmental monitoring and for disaster prediction in the course of mining.

The article reports data on continuous indentation of different rank black coal and anthracite. The test specimens are specially prepared, and their faces are differently oriented relative to their bedding planes. Different mechanical behavior of coal and anthracite microcomponents in different planes relative to bedding is identified, and relevant values of elasticity modulus and hardness are determined. The measurements exhibit spatial anisotropy of microlevel mechanical properties of vitrinite and inertinite.

Under discussion is the experimental estimate of an actual power variation range of pneumatic hammer with a ring-type elastic valve arranged in exhaust unit of back-drive cell in order to lock mechanically this cell until exhaust stroke at various values of the hammer travel. The variation ranges of the valve channel cross-section are found to ensure sustained operation of the pneumatic hammer and the minimized air flow rate irrespective of the hammer weight and position (vertical or horizontal) and the ratio of the hammer power-stroke to the hammer power-stroke cell diameter.

The article presents the remote monitoring systems for operation of high-voltage substations and shovels, designed at the Karaganda State Technical University and introduced at Shubarkol-Komir open pit coal mine. The systems measure power consumption parameters (high-voltage substations and shovels) and controls power consumers and electrical protection. The high-voltage substation monitoring systems transmit data via rf modem, the shovel operation monitoring systems use GPRS modems to transmit data via Internet to a central operator office. In the course of trial operation of the remote monitoring systems, it was succeeded to save power owing to elimination of idle operation of heavy-duty mining machines; moreover, the scope of the continuous control covered power consumption and electric protection at substations and on shovels.

The authors present the schematic circuit of the new-generation compression/vacuum impact machine (CVIM) and its operation using an adjustable magnetic lock, which allows varying the machine power performance and extends the machine capacities in mining, construction and seismic exploration. The operational cycle of CVIM is tested. The authors determine technical parameters of the machine and mechanisms of interaction between the lock, striking unit, air reserve tank and compressed air source. CVIM unit blow energy is estimated at different space positions of the machine. The field trial has assisted in denoting ways of further improvement of the machine.

The authors develop a version of a compound technology with consolidating backfilling and caving for thick flat body of polymetals. Numerical evaluation shows that the technology with the cover caving above consolidating backfill ensures higher safety of mining.

The described technology and equipment enable eliminating drilling-and-blasting in open pit mining. The authors also discuss usability of transfer bins with vibrating discharge in combination with intermodal transport and adaptability of vibratory machines to dump truck-aided stockpiling.

The authors give basic design procedures for two-level rock bolt support in underground mining in permafrost regions. The use of rock bolting in combination with heat insulation on a test site in Dzhebariki-Khaya Coal Mine is studied.